#include <bits/stdc++.h>
using namespace std;

using int64 = long long;
using uint64 = unsigned long long;

int main()
{
    int N;
    int64 X;
    cin >> N >> X;

    map<int, int64> counter;
    vector<int64> a(N);
    for (int i = 0; i < N; i++)
    {
        cin >> a[i];
        counter[a[i]]++;
    }

    int64 ans = 0;
    for (auto mp : counter)
    {
        if (counter.count(X - mp.first) == 0) continue;
        ans += counter[mp.first] * counter[X - mp.first];
    }

    cout << ans << endl;

    return 0;
}